Silicone polyether surfactants

ABSTRACT

The present invention relates to a siloxane-oxyalkylene copolymer surfactant having the formula MD x  D&#39; y  M wherein M represents (CH 3 ) 3  SiO 1/2  or R(CH 3 ) 2  SiO 1/2 , D represents (CH 3 ) 2  SiO 2/2 , D&#39; represents (CH 3 )RSiO 2/2 , and the value of x+y is from 48 and 220, and the ratio x/y is from 5 to 15 inclusive. In the above formulae for M and D&#39;, R is a polyether-containing substituent selected from the group consisting of (1)--C n  H 2n  O(C 2  H 4  O) a  (C 3  H 6  O) b  R&#39; moieties having weight average molecular weights of from about 2300-3200 and wherein n is 3-4, the ratio a/b is from 0.5 to 1.3 inclusive, R&#39; represents hydrogen, an alkyl group of 1-4 carbon atoms or --C(O)CH 3  and (2)--C n&#39;  H 2n&#39;  O(C 2  H 4  O) a&#39;  (C 3  H 6  O) b&#39;  R&#39; moieties having weight average molecular weights of from about 1150-1400 and wherein n&#39; is 3-4, a&#39; is a number such that the ethylene oxide residues constitute 30-100% by weight of the alkylene oxide residues of the polyether, b&#39; is a number such that the propylene oxide residues constitute 0-70% by weight of the alkylene oxide residues of the polyether, R&#39; represents hydrogen, an alkyl group of 1-4 carbon atoms or --C(O)CH 3 , and the blend average molecular weight of the overall polyether-containing substituents R in the compositions is from about 1500 to 2200 and the overall EO/PO molar ratio is from about 0.65 to 1.2. The siloxane-oxyalkylene copolymer surfactants are useful in producing flexible polyurethane slabstock foams.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a continuation-in-part of Ser. No. 08/762,846, filed Dec. 10,1996, now U.S. Pat. No. 5,830,970 which is a continuation-in-part ofSer. No. 08/577,588, filed Dec. 22, 1995, now abandoned.

FIELD OF THE INVENTION

This invention relates to silicone surfactants, and more specifically tosilicone polyether surfactants having a siloxane backbone andoxyalkylene pendant groups. The surfactants of the present invention areuseful in the manufacture of flexible polyurethane foams.

BACKGROUND OF THE INVENTION

In polyurethane foam manufacturing, surfactants are required tostabilize the foam until the polymer-forming chemical reactions aresufficiently complete so that the foam is self-supporting and does notsuffer objectionable collapse.

Silicone polyether surfactants for polyurethane foam manufacture aretypically materials having siloxane backbones and pendant polyethergroups. They are of two types, nonhydrolyzable and hydrolyzable. Thenonhydrolyzable surfactants, in which the pendant polyether groups areattached to the siloxane backbone via Si--C bonds, are generallybelieved to provide high efficiencies but poor processing latitudes.Hydrolyzable surfactants, in which the pendant polyether groups areattached to the siloxane backbone via Si--OC bonds, are generallybelieved to have poor efficiencies but wide processing latitudes.

SUMMARY OF THE INVENTION

The present invention provides nonhydrolyzable silicone surfactantswhich provide excellent emulsification, efficiency and broad processinglatitude in the formation of flexible polyurethane slabstock foams,especially in slabstock foam formulations containing high water levelsand low isocyanate indices. Moreover, flexible polyurethane slabstockfoams produced with a silicone surfactant of the present inventionshowed better foam heights, while maintaining finer cell structures,than foams produced with other surfactants.

The surfactants of this invention are compositions of matter having theaverage formula MD_(x) D'_(y) M wherein M represents (CH₃)₃ SiO_(1/2) orR(CH₃)₂ SiO_(1/2), D represents (CH₃)₂ SiO_(2/2), D' represents(CH₃)RSiO_(2/2), the value of x+y is from 48 to 220, and the ratio x/yis from 5 to 15 inclusive. In the above formula for M and D', R is apolyether-containing substituent selected from the group consisting of

(1)--C_(n) H_(2n) O(C₂ H₄ O)_(a) (C₃ H₆ O)_(b) R' moieties having weightaverage molecular weights of from about 2300-3200 and wherein n is 3-4,the ratio a/b is from 0.5 to 1.3 inclusive, R' represents hydrogen, analkyl group of 1-4 carbon atoms or --C(O)CH₃ and

(2) --C_(n') H_(2n') O(C₂ H₄ O)_(a') (C₃ H₆ O)_(b') R' moieties havingweight average molecular weights of from about 1150-1400 and wherein n'is 3-4 a' is a number such that the ethylene oxide residues constitute30-100% by weight of the alkylene oxide residues of the polyether, b' isa number such that the propylene oxide residues constitute 0-70% byweight of the alkylene oxide residues of the polyether, R' representshydrogen, an alkyl group of 1-4 carbon atoms or --C(O)CH₃.

Further the surfactant compositions MD_(x) D'_(y) M of the inventioncontain polyether-containing substituents R having weight averagemolecular weights of from about 2300-3200 and polyether-containingsubstituents R having weight average molecular weights of from about1150-1400, and the blend average molecular weight of the overallpolyether-containing substituents R in the compositions MD_(x) D'_(y) Mis from about 1500-2200, and the overall ratio of ethylene oxide (EO)residues in both polyethers to propylene oxide (PO) residues in bothpolyethers, i.e., the overall EO/PO molar ratio, is from about 0.65-1.2.

DETAILED DESCRIPTION OF THE INVENTION

The surfactants of this invention are compositions of matter having theaverage formula MD_(x) D'_(y) M wherein M represents (CH₃)₃ SiO_(1/2) orR(CH₃)₂ SiO_(1/2), D represents (CH₃)₂ SiO_(2/2), D' represents(CH₃)RSiO_(2/2), and the value of x+y is from 48 to 220, and the ratiox/y is from 5 to 15 inclusive. In the above formulae for M and D', R isa polyether-containing substituent selected from the group consisting of

(1) --C_(n) H_(2n) O(C₂ H₄ O)_(a) (C₃ H₆ O)_(b) R' moieties havingweight average molecular weights of from about 2300-3200 and wherein nis 3-4, the ratio a/b is from 0.5 to 1.3 inclusive, R' representshydrogen, an alkyl group of 1-4 carbon atoms or --C(O)CH₃ and

(2) --C_(n') H_(2n') O(C₂ H₄ O)_(a') (C₃ H₆ O)_(b') R' moieties havingweight average molecular weights of from about 1150-1400 and wherein n'is 3-4, a' is a number such that the ethylene oxide residues constitute30-100% by weight of the alkylene oxide residues of the polyether, b' isa number such that the propylene oxide residues constitute 0-70% byweight of the alkylene oxide residues of the polyether, and R'represents hydrogen, an alkyl group of 1-4 carbon atoms or --C(O)CH₃.Further the surfactant compositions MD_(x) D'_(y) M of the inventioncontain polyether-containing substituents R having weight averagemolecular weights of from about 2300-3200 and polyether-containingsubstituents R having weight average molecular weights of from about1150-1400, and the blend average molecular weight of thepolyether-containing substituents R in the compositions MD_(x) D'_(y) Mis from about 1500-2200, and the overall ratio of ethylene oxide topropylene oxide residues, i.e., the overall EO/PO molar ratio, is fromabout 0.65-1.2.

Within the broad range of compositions of the invention as defined are anumber of preferred materials. The preferred material has the generalaverage formula MD₄₄₋₆₃ D'₅.5-12.5 M. A most preferred material withinthis class has the general average formula MD₆₀₋₆₂ D'₇₋₈ M. Thepolyether-containing substituents R having weight average molecularweights of from about 2300-3200, and preferably from about 2300-3100,are preferably --C₃ H₆ O(C₂ H₄ O)_(a) (C₃ H₆ O)_(b) R' moieties with ana/b ratio of 1.0 and having a weight average molecular weight of about3100. R' is preferably --C(O)CH₃.

The polyether-containing substituents R having weight average molecularweights of from about 1150-1400, and preferably from about 1200-1400,are preferably --C₃ H₆ O(C₂ H₄ O)_(a) (C₃ H₆ O)_(b) R' moietiescontaining about 43% by weight of ethylene oxide residues and having aweight average molecular weight of about 1250. R' is preferably--C(O)CH₃.

The blend weight average molecular weight of the polyether-containingsubstituents R in the composition MD_(x) D'_(y) M is preferably fromabout 1650-1900. The overall average EO/PO molar ratio is preferablyabout 1.0.

Procedures for synthesizing nonhydrolyzable surfactants havingpolyalkylene oxide pendant groups are well known. Representativedisclosures are provided in U.S. Pat. Nos. 4,147,847 and 4,855,379,which are hereby incorporated by reference.

Typically, the surfactants of the invention are prepared by causing apolyhydridosiloxane of generalized average formula M*D_(x) D"_(y) M* toreact with an appropriately chosen blend of allyl oxyalkylene polyethersin the presence of a hydrosilylation catalyst such as chloroplatinicacid. In the formula for the polyhydridosiloxane, M* is (CH₃)₃ SiO_(1/2)or (H)(CH₃)₂ SiO_(1/2), D is as defined above, and D" is(CH₃)(H)SiO_(2/2). The allyl oxyalkylene polyethers are polyethershaving a terminal vinyl group and containing multiple units derived fromethylene oxide, propylene oxide, or both. The reagents are mixed,generally in a solvent such as toluene or isopropanol (2-propanol),heated to about 70°-85° C., then the catalyst is added, a temperaturerise of about 10-15° C. is observed, and the mixture is finally sampledand analyzed for SiH groups by adding alcohol and base and measuringevolved hydrogen. If a volatile solvent is used, it is removed byvacuum.

The polyhydridosiloxanes having the average formula M*D_(x) D"_(y) M*are prepared in the manner known to the art. For the case in which M* is(CH₃)₃ SiO_(1/2), an alkyldisiloxane such as hexamethyldisiloxane, apolyhydridosiloxane polymer, and an alkylcyclosiloxane such asoctamethylcyclotetrasiloxane are reacted in the presence of a strongacid such as sulfuric acid. For the case in which M* is (H)(CH₃)₂SiO_(1/2), a hydridoalkyldisiloxane such asdihydridotetramethyldisiloxane, a polyhydridosiloxane polymer, and analkylcyclosiloxane such as octamethylcyclotetrasiloxane are reacted inthe presence of a strong acid such as sulfuric acid.

The allyl oxyalkylene polyethers, also referred to as polyethers, arelikewise prepared in a manner known to the art. An allyl alcohol,optionally bearing a substituent on the 1- or 2-position, is combinedwith ethylene oxide, propylene oxide, or both, in the presence of a basecatalyst, to yield the desired polyether with a terminal hydroxyl group.This is typically capped by further reaction with an alkylating oracylating agent such as a methyl halide or acetic anhydride,respectively, to obtain an alkoxy or acetyl end group. Other end capsmay of course be employed, including hydrogen, alkoxy groups or alkyl oraryl groups.

The surfactants of the invention are employed in the manufacture offlexible polyurethane foam in the manner known to the art. In producingthe polyurethane foams using the surfactants of this invention, one ormore polyols, preferably polyalkylene ether polyols, are employed forreaction with a polyisocyanate to provide the urethane linkage. Suchpolyols have an average of typically 2.1 to 3.5 hydroxyl groups permolecule. Illustrative of suitable polyols as a component of thepolyurethane composition are the polyalkylene ether and polyesterpolyols. The preferred polyalkylene ether polyols include thepoly(alkylene oxide) polymers such as poly(ethylene oxide) andpoly(propylene oxide) polymers and copolymers with terminal hydroxylgroups derived from polyhydric compounds, including diols and triols;for example, among others, ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butane diol, 1,6-hexane diol, neopentyl glycol, diethyleneglycol, dipropylene glycol, pentaerythritol, glycerol, diglycerol,trimethylol propane and like low molecular weight polyols.

In the practice of this invention, a single high molecular weightpolyether polyol may be used. Also, mixtures of high molecular weightpolyether polyols such as mixtures of di- and trifunctional materialsand/or different molecular weight or different chemical compositionmaterials may be used.

Useful polyester polyols include those produced by reacting adicarboxylic acid with an excess of a diol, for example, adipic acidwith ethylene glycol or butanediol, or reacting a lactone with an excessof a diol such as caprolactone with propylene glycol.

In addition to the polyether and polyester polyols, the masterbatches,or premix compositions, frequently contain a polymer polyol. Polymerpolyols are used in polyurethane foam to increase the foam's resistanceto deformation, i.e. to increase the load-bearing properties of thefoam. Currently, two different types of polymer polyols are used toachieve load-bearing improvement. The first type, described as a graftpolyol, consists of a triol in which vinyl monomers are graftcopolymerized. Styrene and acrylonitrile are the usual monomers ofchoice. The second type, a polyurea modified polyol, is a polyolcontaining a polyurea dispersion formed by the reaction of a diamine andTDI. Since TDI is used in excess, some of the TDI may react with boththe polyol and polyurea. This second type of polymer polyol has avariant called PIPA polyol which is formed by the in-situ polymerizationof TDI and alkanolamine in the polyol. Depending on the load-bearingrequirements, polymer polyols may comprise 20-80% of the polyol portionof the masterbatch.

The polyurethane products are prepared using any suitable organicpolyisocyanates well known in the art including, for example,hexamethylene diisocyanate, phenylene diisocyanate, toluene diisocyanate("TDI") and 4,4'-diphenylmethane diisocyanate ("MDI"). Especiallysuitable are the 2,4- and 2,6-TDI's individually or together as theircommercially available mixtures. Other suitable isocyanates are mixturesof diisocyanates known commercially as "crude MDI", also known as PAPI,which contain about 60% of 4,4'-diphenylmethane diisocyanate along withother isomeric and analogous higher polyisocyanates. Also suitable are"prepolymers" of these polyisocyanates comprising a partially prereactedmixture of a polyisocyanates and a polyether or polyester polyol.

Suitable urethane catalysts useful in the present invention are allthose well known to the worker skilled in the art including tertiaryamines such as triethylene diamine, N-methylmorpholine,N-ethylmorpholine, triethylamine, tributylamine, triethanolamine,dimethylethanolamine and bisdimethylaminodiethylether, and organotinssuch as stannous octoate, stannous acetate, stannous oleate, stannouslaurate, dibutyltin dilaurate, and other such tin salts.

Other typical agents which may be found in the flexible polyurethanefoam formulations include chain extenders such as ethylene glycol andbutanediol; crosslinkers such as diethanolamine, diisopropanolamine,triethanolamine and tripropanolamine; and especially blowing agents suchas water, liquid carbon dioxide, acetone, pentane, trichloroethane,methylene chloride, trichlorofluoromethane, and the like.

Other additives may of course be employed to impart specific propertiesto the foam. Examples are materials such as flame retardants, colorants,fillers and hardness modifiers.

The polyurethane foams of this invention may be formed in accordancewith any of the processing techniques known to the art, such as, inparticular, the "one shot" technique. In accordance with this method,foamed products are provided by carrying out the reaction of thepolyisocyanate and polyol simultaneously with the foaming operation. Itis sometimes convenient to add the surfactant to the reaction mixture asa premixture with one or more of the blowing agent, polyol, water, andcatalyst components.

It is to be understood that the relative amounts of the variouscomponents of the foam formulation are not narrowly critical. The polyoland polyisocyanate are present in the foam-producing formulation in themajor amount. The relative amounts of these two components in themixture are well known to the art. The blowing agent, catalysts, andsurfactant are each present in a minor amount sufficient to foam thereaction mixture. The catalysts are present in a catalytic amount, i.e.,that amount necessary to catalyze the reactions to produce the urethaneand urea at a reasonable rate, and the surfactant is present in theamount sufficient to impart the properties desired and to stabilize thereacting foam, for example, 0.4 to 2 pphpp.

In a typical preparation, the polyol, water, surfactant, amine catalyst,and optional blowing agent are blended together, then the tin catalystis added with stirring, and finally toluene diisocyanate is mixed in andthe composition is allowed to foam and polymerize.

The flexible polyurethane foams produced in accordance with the presentinvention can be used in the same area as conventional polyurethanefoams. For example, the foams of the present invention can be used withadvantage in the manufacture of textile interliners, cushions,mattresses, padding, carpet underlay, packaging, gaskets, sealers,thermal insulators and the like.

A general polyurethane flexible slabstock foam formulation containingthe silicone surfactants according to the invention would comprise thefollowing components in parts by weight:

Flexible Slabstock Foam Formulation

Polyol 100

Silicone Surfactant 0.4-2

Water 2-7

Auxiliary Blowing Agent 0-20

Amine Urethane Catalyst 0.05-0.3

Tin Urethane Catalyst 0.1-0.35

Isocyanate Index 85-120

(preferably TDI)

In a preferred flexible slabstock foam formulation the water level is6-7 pphpp and the isocyanate is TDI at an index in the range of about 80to less than 100.

EXAMPLES

In the following examples the foams were made in accordance with thefollowing formulation and procedure:

Voranol 3137 polyol 100.00 pphpp

Water 6.50 pphpp

DABCO® CS90 amine 0.10 pphpp

DABCO T-10 tin 0.32 pphpp

Silicone Surfactant 0.60 pphpp

TDI (95 Index) 67.66 pphpp

pphpp=parts per hundred parts polyol

1) For each foam a corrugated box having dimensions 14×14×14 inches(35.6×35.6×35.6 cm) was prepared. Alternatively, a polyethylene linerwas prepared and inserted into a 3.5 gallon (13.3 liter) bucket.

2) A premix was prepared for each series of foams. The premix containedVoranol 3137 polyol (from Dow Chemical Company), water, and DABCO CS90amine catalyst (from Air Products and Chemicals, Inc.).

3) Premix was weighed into a 48 ounce (1.42 liter) paper cup andsilicone surfactant was added.

4) In a separate 250 mL plastic beaker, TDI (toluene diisocyanate) wasweighed.

5) DABCO T-10 catalyst (from Air Products and Chemicals, Inc.) was addedto the premix cup and mixed for 10 seconds with an electronic mixer at2000 rpm. DABCO T-10 catalyst is a 50% dilution of stannous octoate.

6) The contents of the TDI beaker were poured into the premix cup andimmediately mixed for 7 seconds with an electronic mixer at 2000 rpm.

7) A stopwatch was started when the electronic mixer started to mix thecontents of the cup containing premix and TDI.

8) The mixture was poured into the container keeping the lip of the cupas close to the bottom of the container as possible to avoid splashing.

9) The remaining material in the cup was weighed.

10) For each foam the following data was obtained: full rise time, fullrise height, and full cure height after 16 hours.

11) The foams were sectioned after 16 hours. Samples of dimensions 2×2×1inch (5.08×5.08×2.54 cm) were taken from the top and the bottom of thefoam for airflow and density determinations. The bottom section wastaken 1.5 inches (3.81 cm) from the bottom of the foam. The top sectionwas taken 7.5 inches (19.05 cm) from the bottom of the foam.

Example 1

Polyurethane foams were made in accordance with the procedures describedabove using the following surfactants. These foams were made using theboxes.

Surfactants A and B are proprietary commercial silicone surfactantsavailable from OSi Specialties, Inc. They were used for comparisonpurposes.

Surfactants C and D are proprietary commercial silicone surfactantsavailable from Th Goldschmidt AG. They were used for comparisonpurposes.

Surfactant E is a proprietary commercial silicone surfactant availablefrom Air Products and Chemicals, Inc. It was used for comparisonpurposes.

Surfactant F is a silicone surfactant of the present invention having asiloxane backbone with x+y=68 and a target x/y ratio of 8. Twopolyether-containing substituents with --C(O)CH₃ endgroups are pendant.The first, present in 35% by weight of the total, has an approximatemolecular weight of 3100 and an a/b ratio of 1.0. The second, present in65% by weight of the total, has an approximate molecular weight of 1250and an a'/b' ratio of 1.0.

The performance of foams prepared using each of the above surfactants isdescribed in Table 1. In Table 1, the terms have the following meanings:

"Full Rise Height" is the maximum height in millimeters obtained duringthe rise of the foam.

"Full Cure Height" is the maximum height in millimeters of the foamafter curing at room temperature for 16-24 hours.

"% Sighback"=100×(Full Rise Height-Full Cure Height) Full Rise Height

"Top Airflow"=Airflow at a backpressure of 0.5 inches (12.7 mm) of waterin ft³ /min through a foam sample having dimensions 2×2×1 inch(5.08×5.08×2.54 cm) taken from the top section of the foam.

"Bottom Airflow"=Airflow at a backpressure of 0.5 inches (12.7 mm) ofwater in ft³ /min through a foam sample having dimensions 2×2×1 inch(5.08×5.08×2.54 cm) taken from the bottom section of the foam.

"Cell Count"=average number of cells per linear inch (2.54 cm) of thefoam sample.

                  TABLE 1                                                         ______________________________________                                               Full    Full                                                              Rise Cure % Top Bottom Cell                                                  Surfactant Height Height Sighback Airflow Airflow Count                     ______________________________________                                        A      276.7   268.2   3.07   1.6    1.6    9                                   B 271.9 264.2 2.83 8.4 4.3 25                                                 C 260.7 251.0 3.72 7.5 3.4 25                                                 D 287.9 280.2 2.67 3.6 2.1 16                                                 E 271.6 262.7 3.28 2.1 2.0  6                                                 F 287.3 278.2 3.17 7.1 4.3 26                                               ______________________________________                                    

Table 1 shows that surfactants A, D, and E give foams with low airflowsand large cells. Surfactants B and C provide good airflow and cellstructure, but give foams of low height. Only surfactant F of thepresent invention provides foam with fine cell structure, high airflow,and high heights, all the requisite attributes of a good flexible foam.

Example 2

Polyurethane foams were made in accordance with the procedures describedabove using the surfactants described in Table 2 (these foams were madein the buckets). The surfactants are compounds having the generalformula MD_(x) D'_(y) M wherein M denotes (CH₃)₃ SiO_(1/2), D denotes(CH₃)₂ SiO_(2/2), D' denotes (CH₃)RSiO_(2/2), R is apolyether-containing substituent selected from the group consisting of:

(1) --C₃ H₆ O(C₂ H₄ O)_(a) (C₃ H₆ O)_(b) C(O)CH₃ having a weight averagemolecular weight of about 3100 and

(2) --C₃ H₆ O(C₂ H₄ O)_(a') (C₃ H₆ O)_(b') C(O)CH₃ having a weightaverage molecular weight about 1250.

The values of x, y, a, b, a', b', the blend average molecular weight ofthe polyether-containing substituents R in the composition, and theoverall EO/PO molar ratio for each of the surfactants is delineated inTable 2 below.

                  TABLE 2                                                         ______________________________________                                                                              Average                                                                              Overall                                   Polyether EO/PO                                                        Surfactant x y a b a' b' MW molar ratio                                     ______________________________________                                        F      60.4    7.6    30  30  12  12  1664   1                                  G 60.4 7.6 30 30 12 12 1500 1                                                 H 60.4 7.6 30 30 12 12 1727 1                                                 I 56.7 11.3  30 30 12 12 1500 1                                               J 56.7 11.3  30 30 12 12 1727 1                                               K 42.7 5.3 30 30 12 12 1500 1                                                 L 42.7 5.3 30 30 12 12 1727 1                                                 M 40.0 8.0 30 30 12 12 1500 1                                                 N 40.0 8.0 30 30 12 12 1727 1                                                 O 51.6 6.4 30 30 12 12 1664 1                                                 P 51.6 6.4 30 30 12 12 1795 1                                                 Q 60.4 7.6 30 30 12 12 1795 1                                                 R 56.0 7.0 30 30 12 12 1727 1                                                 S 54.6 8.4 30 30 12 12 1605 1                                                 T 54.0 9.0 30 30 12 12 1605 1                                                 U 54.0 9.0 25 25 12 12 1560 1                                                 V 54.0 9.0 30 30 15 15 1909 1                                                 W 54.0 9.0 30 30 18 18 2193 1                                                 X 169.0  23.0  18 18 12  0 1477   1.4                                       ______________________________________                                    

The use of Surfactants F-W in the foam formulation resulted in all ofthese surfactants affording good foams. Surfactant X, which had anoverall EO/PO molar ratio of 1.4, afforded a foam having coarse cellsand low air flow.

Example 3

Polyurethane foams were made in accordance with the procedures describedabove using the surfactants described in Table 3. The surfactants hadthe same general formula as those employed in Example 2. The values ofx, y, a, b, a', b', the blend average molecular weight of thepolyether-containing substituents R in the composition, and the overallEO/PO molar ratio for each of the surfactants is delineated in Table 3below.

                  TABLE 3                                                         ______________________________________                                                                             Average                                                                              Overall                                    Polyether EO/PO                                                        Surfactant x y a b a' b' MW molar Ratio                                     ______________________________________                                        Y       60.4   7.6   30  30   8  15  1866   0.74                                Z 60.4 7.6 30 30  8 15 1662 0.68                                              A' 60.4 7.6 30 30  8 15 1498 0.61                                             B' 60.4 7.6 30 30 10  4 1242 1.53                                             C 60.4 7.6 30 30 10  4  910 2.03                                              D' 60.4 7.6 30 30 10  4 1050 1.76                                             E' 60.4 7.6 30 30 12 12 1333 1.00                                             F' 60.4 7.6 30 30 12 12 1434 1.00                                             G' 60.4 7.6 30 30 12 12 1640 1.00                                             H' 60.4 7.6 30 30 12 12 1916 1.00                                           ______________________________________                                    

The foams were then measured for full rise height, full cure height, %Sighback, top airflow, and bottom airflow according to the proceduresdescribed hereinabove. The results of the measurements are reported inTable 4 below.

                  TABLE 4                                                         ______________________________________                                               Full Rise Full Cure                                                                              %       Top   Bottom                                  Surfactant Height Height Sighback Airflow Airflow                           ______________________________________                                        Y      351.10    324.43    7.60   7.56  6.17                                    Z 327.46 268.28 18.07 6.21 5.54                                             A'     FINE CELLED TOTAL COLLAPSE                                             B'     336.15    282.84   15.86   2.64  3.14                                  C'     COARSE CELLED TOTAL COLLAPSE                                             D' COARSE CELLED TOTAL COLLAPSE                                             E'     313.80     90.00   71.32   --    --                                      F' 337.03 228.56 32.19 5.15 4.49                                              G' 342.68 320.28  6.54 6.63 5.40                                              H' 346.23 322.57  6.83 7.07 6.30                                            ______________________________________                                    

The use of the surfactants of this invention in the foam formulationresulted in good foams in contrast to surfactants A'-F' which eithercollapsed or had poor foam characteristics.

That which is claimed is:
 1. A composition of matter having the formula

    MD.sub.x D'.sub.y M

wherein M represents (CH₃)₃ SiO_(1/2) or R(CH₃)₂ SiO_(1/2), D represents(CH₃)₂ SiO_(2/2), D' represents (CH₃)RSiO_(2/2), and the value of x+y isfrom 48 to 220, and the ratio x/y is from 5 to 15 inclusive, wherein inthe above formulae for M and D', R is a polyether-containing substituentselected from the group consisting of: (1) --C_(n) H_(2n) O(C₂ H₄ O)_(a)(C₃ H₆ O)_(b) R' moieties having weight average molecular weights offrom 2300-3200 and wherein n is 3-4, the ratio a/b is from 0.5 to 1.3inclusive, R' represents hydrogen, an alkyl group of 1-4 carbon atoms,or --C(O)CH₃ and (2) --C_(n') H_(2n') O(C₂ H₄ O)_(a') (C₃ H₆ O)_(b') R'moieties having weight average molecular weights of from 1150-1400 andwherein n' is 3-4, a' is a number such that the ethylene oxide residuesconstitute 30-100% by weight of the alkylene oxide residues of thepolyether, b' is a number such that the propylene oxide residuesconstitute 0-70% by weight of the alkylene oxide residues of thepolyether, R' represents hydrogen, an alkyl group of 1-4 carbon atoms or--C(O)CH₃,and the blend average molecular weight of thepolyether-containing substituents R in the composition is from 1500 to2200 and the overall EO/PO molar ratio is from 0.65 to 1.2.
 2. Acomposition of matter according to claim 1, wherein the value of x+y is68, the ratio x/y is 8, and R comprises a first polyether-containingsubstituent at 35 wt %, having a weight average molecular weight of3100, and an a/b ratio of 1.0, and a second polyether-containingsubstituent at 65 wt %, having a weight average molecular weight of1250, and an a'/b' ratio of 1.0.
 3. A composition of matter according toclaim 1, wherein x has a value of 44 to 63 and y has a value of 5.5 to12.5.
 4. A composition of matter according to claim 1, wherein x has avalue of 60 to 62 and y has a value of 7 to
 8. 5. A composition ofmatter according to claim 1, wherein R' is --C(O)CH₃.
 6. A compositionof matter according to claim 2, wherein R' is --C(O)CH₃.
 7. Acomposition of matter according to claim 3, wherein R' is --C(O)CH₃. 8.A composition of matter according to claim 4, wherein R' is --C(O)CH₃.9. A composition according to claim 1, wherein (1) is a --C_(n) H_(2n)O(C₂ H₄ O)_(a) (C₃ H₆ O)_(b) R' moiety having weight average molecularweights of from 2300-3100.
 10. A composition according to claim 1,wherein (2) is a --C_(n') H_(2n') O(C₂ H₄ O)_(a') (C₃ H₆ O)_(b') R'moiety having weight average molecular weights of from 1200-1400.
 11. Acomposition according to claim 9, wherein (2) is a --C_(n') H_(2n') O(C₂H₄ O)_(a') (C₃ H₆ O)_(b') R' moiety having weight average molecularweights from 1200-1400.
 12. A composition of matter according to claim1, wherein (2) is a --C₃ H₆ O(C₂ H₄ O)_(a) (C₃ H₆ O)_(b) R' moietycontaining 43% by weight of ethylene oxide residues and having a weightaverage molecular weight of
 1250. 13. A composition of matter accordingto claim 12, wherein R' is --C(O)CH₃.
 14. A composition of matteraccording to claim 1, wherein the blend weight average molecular weightof the polyether-containing substituents R in the composition is from1650-1900.
 15. A composition of matter according to claim 1, wherein theoverall average EO/PO molar ratio is 1.0.